-67.19% is the change from 506 to 166
Calculation steps:
[( 166 - 506 ) ÷ 506] x 100 = -67.19%
Formula
Percentage change = [(166 - 506) / 506] x 100
Subtract the new number by the original number
166 - 506 = -340
-340 ÷ 506 = -0.6719367588932806
-0.6719367588932806 x 100 = -67.19%